如何测试swift嵌套函数？

How do you write test for swift nested function?

你如何为swift嵌套函数编写测试?

Since the function is inside another function, I don't know how to call it from outside.

由于该函数在另一个函数内部,我不知道如何从外部调用它。

I'm using nested function because I can't call a private self function in init

我正在使用嵌套函数,因为我无法在init中调用私有自身函数

2 个解决方案

#1

You shouldn't test nested function, just like you shouldn't test private methods, from Bad Testing Practices:

你不应该测试嵌套函数,就像你不应该测试私有方法一样,来自Bad Testing Practices:

Private means private. Period. If you feel the need to test a private method, there is something conceptually wrong with that method. Usually it is doing too much to be a private method, which in turn violates the Single Responsibility Principle.

私人意味着私人。期。如果您觉得需要测试私有方法,那么该方法在概念上是错误的。通常,做私人方法做得太多,而后者又违反了单一责任原则。

#2

Continuing the point from Code Different, from a testing point of view, the following code is identical:

继续从Code Different开始,从测试的角度来看,以下代码是相同的:

// Without nesting
func f() {
    // Do things
    // Do other things we want to test
    // Do more things
}

// With nesting
func fnest() {
    func nest() {
        // Do other things we want to test
    }

    // Do things
    nest()
    // Do more things
}

Whatever technique you'd use to test "Do other things we want to test" in f() is precisely the same technique that you'd use to test it in fnest(). If the piece you want to test is insufficiently accessible, in either case you must redesign (or change your testing goal), but there's nothing special about nested functions.

无论你用什么技术来测试f()中的“我们想要测试的其他东西”,都是用来在fnest()中测试它的技术。如果要测试的部分不够容易访问,在任何一种情况下都必须重新设计(或更改测试目标),但嵌套函数没有什么特别之处。

I'm using nested function because I can't call a private self function in init

我正在使用嵌套函数,因为我无法在init中调用私有自身函数

If this is the entire problem, then make the function static and pure. Rather than passing self, pass the data required to perform the calculation, and return the result. Then modify self inside of init rather than in the function.

如果这是整个问题,那么使函数静态和纯。而不是传递self,传递执行计算所需的数据,并返回结果。然后修改init内部的self而不是函数。

#1